What Causes Car Air Conditioning Leakage?
3 Answers
The reasons for water leakage in car air conditioning include improper installation of the unit, poor drainage pipe, condensation on the piping, and heat exchanger dripping. Improper installation of the unit: Usually, the indoor unit is tilted, and the direction of the pipe opening is too high. Solution: Re-adjust the direction of the indoor unit to resolve the issue. Poor drainage pipe: Due to a loose or wavy-shaped drainage pipe, drainage is hindered. Solution: Check the drainage pipe's flow path and ensure the connection between the drainage pipe and the air conditioning pipe is proper. Condensation on the piping: If the insulation material on the piping is of poor quality or too thin, condensation occurs when the refrigerant passes through. Solution: Replace the insulation material. Heat exchanger dripping: Dust accumulation on the heat exchanger causes uneven temperature distribution, leading to water droplets forming midway on the heat exchanger. Water droplets falling outside the drip pan will drip indoors. Insufficient refrigerant in the air conditioning system can cause indoor icing, and the melted ice forms water droplets that do not directly fall into the drip pan. Solution: Clean the dust on the heat exchanger and replenish the refrigerant. Air conditioning maintenance: It is necessary to regularly replace the air conditioning filter. Its key role is to prevent wind and dust from entering the pipeline, so during normal maintenance, the replacement of the air filter is particularly important. Especially in environments with poor air quality, car owners need to follow the car maintenance instructions and combine it with seasonal adjustments for winter and summer, regularly maintaining and replacing the air filter.
Last time, my car's AC leaked and completely soaked the passenger side floor mat—what a headache. Actually, this is mostly caused by a clogged drain pipe. When the AC cools, the evaporator condenses water droplets, which should flow out through a plastic drain tube to the underside of the car. If dust or leaves accumulate in the pipe, the water can back up and seep into the cabin. My Volkswagen had water stains under the passenger seat when parked, but it was fixed by blowing out the pipe with a high-pressure air gun. However, be aware that if the undercarriage has been damaged, it might deform the pipe, or some cars may have misaligned pipes due to poor assembly, leading to leaks. By the way, prolonged leakage can cause the cabin floor to mold or rust, so don’t ignore water stains. If you can’t locate the drain outlet, it’s easier to just take it to a repair shop and lift the car for inspection.
I remember my car's AC vents suddenly dripping water, and the mechanic said it was condensation from the evaporator not draining properly. Specifically, there are a few scenarios: First, a dirty cabin air filter reduces airflow, causing the evaporator to retain more cold and frost over, which then melts into water inside the cabin after parking. Second, the drain tube may have aged and cracked, especially in older cars where rubber tubes are prone to issues. Third, the drain hole might be positioned higher than the evaporator, preventing water from draining at all. At the time, he had me pop the hood to check the drain tube outlet behind the radiator, and sure enough, it was clogged with mud. Fixing it yourself is actually quite simple—just use a thin wire to gently clear the blockage. He also reminded me that regularly replacing the cabin air filter can save a lot of hassle.
